A2 June 2025 Paper 1 Q4
4 Which one of the following statements is always correct?
Tick (✓) one box. [1 mark]
- \(\sinh^2 x = \dfrac{1}{2}(1 - \cosh 2x)\)
- \(\operatorname{sech}^2 x + \tanh^2 x = 1\)
- \(\operatorname{cosech}^2 x + \coth^2 x = 1\)
- \(\cosh^2 x = \dfrac{1}{2}(\cosh 2x - 1)\)
| Scheme | Marks | AO |
|---|---|---|
| Ticks 2nd answer. | B1 | 1.1b |
| (1 mark) |
Typical solution
\(\operatorname{sech}^2 x + \tanh^2 x = 1\)